Such a control is known, for example, from DE 100 18 481 A1 (TBT 9905). In that case a number of radio receivers are placed in the longwall face, which are connected in series with a central control in the head gate (longwall face control device). Each radio receiver addressed continuously receives information from the rock sensor and passes on this information to the longwall face control device for evaluation. In the longwall face control device it is then calculated, whether the planer is still traveling in the area of the coal face or breaks already in the boundary layers of the rock. Depending on this, the planer has to be raised or lowered. The raising of the planer (climbing) is carried out by lowering the edge of the chute, whereby the planer tilts about a sliding block, provided in the area of the centre of the width of the chute. The lowering of the planer (plunging) is carried out in reverse in that the edge of the chute, adjacent to the extraction devices, is raised by a tilting device and consequently the planer is pivoted in the opposite direction about the sliding block.
An object of the invention is to make the control so fast, that the position of the planer could be possibly corrected with regard to climbing or plunging while the extraction is still taking place, but in any case during the following return travel.